Single-spin asymmetries in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target.

نویسندگان

  • A Airapetian
  • N Akopov
  • Z Akopov
  • M Amarian
  • A Andrus
  • E C Aschenauer
  • W Augustyniak
  • R Avakian
  • A Avetissian
  • E Avetissian
  • A Bacchetta
  • P Bailey
  • D Balin
  • M Beckmann
  • S Belostotski
  • N Bianchi
  • H P Blok
  • H Böttcher
  • A Borissov
  • A Borysenko
  • M Bouwhuis
  • A Brüll
  • V Bryzgalov
  • G P Capitani
  • M Cappiluppi
  • T Chen
  • G Ciullo
  • M Contalbrigo
  • P F Dalpiaz
  • R De Leo
  • M Demey
  • L De Nardo
  • E De Sanctis
  • E Devitsin
  • P Di Nezza
  • M Düren
  • M Ehrenfried
  • A Elalaoui-Moulay
  • G Elbakian
  • F Ellinghaus
  • U Elschenbroich
  • R Fabbri
  • A Fantoni
  • A Fechtchenko
  • L Felawka
  • S Frullani
  • G Gapienko
  • V Gapienko
  • F Garibaldi
  • K Garrow
  • G Gavrilov
  • V Gharibyan
  • O Grebeniouk
  • I M Gregor
  • C Hadjidakis
  • K Hafidi
  • M Hartig
  • D Hasch
  • M Henoch
  • W H A Hesselink
  • A Hillenbrand
  • M Hoek
  • Y Holler
  • B Hommez
  • I Hristova
  • G Iarygin
  • A Ilyichev
  • A Ivanilov
  • A Izotov
  • H E Jackson
  • A Jgoun
  • R Kaiser
  • E Kinney
  • A Kisselev
  • T Kobayashi
  • M Kopytin
  • V Korotkov
  • V Kozlov
  • B Krauss
  • V G Krivokhijine
  • L Lagamba
  • L Lapikás
  • A Laziev
  • P Lenisa
  • P Liebing
  • L A Linden-Levy
  • W Lorenzon
  • H Lu
  • J Lu
  • S Lu
  • B-Q Ma
  • B Maiheu
  • N C R Makins
  • Y Mao
  • B Marianski
  • H Marukyan
  • F Masoli
  • V Mexner
  • N Meyners
  • T Michler
  • O Mikloukho
  • C A Miller
  • Y Miyachi
  • V Muccifora
  • A Nagaitsev
  • E Nappi
  • Y Naryshkin
  • A Nass
  • M Negodaev
  • W-D Nowak
  • K Oganessyan
  • H Ohsuga
  • A Osborne
  • N Pickert
  • D H Potterveld
  • M Raithel
  • D Reggiani
  • P E Reimer
  • A Reischl
  • A R Reolon
  • C Riedl
  • K Rith
  • G Rosner
  • A Rostomyan
  • L Rubacek
  • J Rubin
  • D Ryckbosch
  • Y Salomatin
  • I Sanjiev
  • I Savin
  • A Schäfer
  • C Schill
  • G Schnell
  • K P Schüler
  • J Seele
  • R Seidl
  • B Seitz
  • R Shanidze
  • C Shearer
  • T-A Shibata
  • V Shutov
  • K Sinram
  • W Sommer
  • M Stancari
  • M Statera
  • E Steffens
  • J J M Steijger
  • H Stenzel
  • J Stewart
  • F Stinzing
  • P Tait
  • H Tanaka
  • S Taroian
  • B Tchuiko
  • A Terkulov
  • A Trzcinski
  • M Tytgat
  • A Vandenbroucke
  • P B van der Nat
  • G van der Steenhoven
  • Y van Haarlem
  • M C Vetterli
  • V Vikhrov
  • M G Vincter
  • C Vogel
  • J Volmer
  • S Wang
  • J Wendland
  • J Wilbert
  • G Ybeles Smit
  • Y Ye
  • Z Ye
  • S Yen
  • B Zihlmann
  • P Zupranski
چکیده

Single-spin asymmetries for semi-inclusive electroproduction of charged pions in deep-inelastic scattering of positrons are measured for the first time with transverse target polarization. The asymmetry depends on the azimuthal angles of both the pion (phi) and the target spin axis (phi(S)) about the virtual-photon direction and relative to the lepton scattering plane. The extracted Fourier component sin((phi+phi(S))(pi)(UT) is a signal of the previously unmeasured quark transversity distribution, in conjunction with the Collins fragmentation function, also unknown. The component sin((phi-phi(S)(pi)(UT) arises from a correlation between the transverse polarization of the target nucleon and the intrinsic transverse momentum of quarks, as represented by the previously unmeasured Sivers distribution function. Evidence for both signals is observed, but the Sivers asymmetry may be affected by exclusive vector meson production.

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منابع مشابه

Azimuthal single-spin asymmetries in semi-inclusive deep-inelastic scattering on a transversely polarised hydrogen target

Azimuthal single-spin asymmetries (SSA) in semi-inclusive electroproduction of charged pions and kaons in deep-inelastic scattering of positrons on a transversely polarised hydrogen target were observed. SSA amplitudes for both the Collins and the Sivers mechanism are presented.

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عنوان ژورنال:
  • Physical review letters

دوره 94 1  شماره 

صفحات  -

تاریخ انتشار 2005